So ive decided that i am going to but new heads. If i use a taperule and measure the dream head not starting from the metalpart on the head but on the front end is that the correctplace to start the measurment??

Ehh. Didn't know if it was someone messin around. I never thought about what your asking because I always knew the drum sizes. If you really don't know what your sizes are, take the heads off and take them to the store when your ready to buy new heads. How about a picture of your set up?

Just get a tape measure and measure the inside diameter of the rims on your drum and it should be pretty close to an even number of inches, if not, just round to the closest inch. That is the size of the head you need.

That way, you'll also know what kind of heads you had previously, and the person selling you the new heads can (hopefully) tell you what the different new heads will sound like compared to what you brought it.